Various types of fluorescent tube circuits have been proposed. Normally, fluorescent tubes are supplied from an alternating current network. In many installations, however, for example in department stores or other public places in which fluorescent tubes are used for general illumination, it is necessary that emergency circuits are provided in case of failure of network power supply. Such emergency circuits usually include a battery, connected through a rectifier to the network, and an inverter circuit which is activated upon failure of network power to then supply the fluorescent tube lighting circuit with alternating voltage pulses.